This energy booster is mostly found in meats and dairy products, so that anyone practicing a vegetarian lifestyle can have shortage of L-carnitine. For these people Vital M-40 Capsules are the best natural energy booster. Spirulina: Spirulina is also one of the best and effective natural energy boosters for men. It is one of the green foods rising to fame. Spirulina contain amino acids, SMART X minerals, vitamins, and…